This invention relates to a flue gas desulfurization system, and in particular to a dissipator for mixing flue gases and lime and ejecting the mixture into a water pool to react the SO.sub.2 in the flue gases with the lime, thereby removing the SO.sub.2 from the flue gases.
Flue gases from the combustion of coal, for example in a power plant, contain varying amounts of SO.sub.2, resulting primarily from the sulfur in the coal. This SO.sub.2 is an undesirable pollutant, responsible for acid rain, and various attempts have been made to remove SO.sub.2 from flue gases. One method involves reacting the SO.sub.2 with lime to make calcium sulfate (CaSO.sub.4). This calcium sulfate can then be disposed of or put to use, for example in making wallboard.
The present invention relates to a dissipator apparatus for mixing powdered lime and flue gases, and ejecting this mixture into a water pool to facilitate the reaction of the lime and the SO.sub.2 in the flue gases, thereby removing the SO.sub.2 from the flue gases. Generally the dissipator of the present invention comprises an elongate tubular body having first and second ends. The first end has an inlet through which the mixture of flue gases and lime is introduced into the dissipator. The second end is generally closed. There are plurality of perforations in the sidewall of the tubular body through which the mixture of flue gases and lime can escape from the dissipator. There is a series of disrupters spaced longitudinally inside the elongate tubular body. Each disrupter comprises a plate with a plurality of baffles mounted on the top surface thereof to facilitate the mixing of the flue gases and powdered lime delivered to the dissipator.
In the preferred embodiment, each disrupter comprises a flat, generally circular plate, and the baffles comprise a plurality of wedge-shaped members, the members being spaced about the circumference of the plate, and oriented with their apices pointing generally toward the center of the plate. The size of the disrupters increases toward the second end of the tubular body, which is preferably concave, and most preferably a hollow blunt cone.
The configuration of the dissipator, and particularly the series of disrupters, causes improved mixing of the flue gases and the powdered lime, facilitating the reaction between the SO.sub.2 in the flue gases and the lime. Thus the dissipator helps to remove a substantial amount of the SO.sub.2 from the flue gases. The dissipator is of simple and reliable construction, and thus is relatively inexpensive to construct and maintain.
These and other features and advantages will be in part apparent, and in part pointed out hereinafter.